Introduction 3 lectures 12:23 Scope of the course preview In this introductory lecture we will understand the contents of the course.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Introduction 3 lectures 12:23 Scope of the course preview In this introductory lecture we will understand the contents of the course.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Scope of the course preview In this introductory lecture we will understand the contents of the course.
Scope of the course preview In this introductory lecture we will understand the contents of the course.
Scope of the course preview In this introductory lecture we will understand the contents of the course.
Scope of the course preview In this introductory lecture we will understand the contents of the course. In this introductory lecture we will understand the contents of the course. In this introductory lecture we will understand the contents of the course.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
What is casting preview Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
Casting is a manufacturing process in which a liquid material is usually poured into a mold
(Casting equipment), which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a
casting/casted component, which is ejected or broken out of the mold to complete the process.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Steps of casting There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
There are six steps in the casting process:
- Place a pattern in sand to create a mold.
- Incorporate the pattern and sand in a gating system.
- Remove the pattern.
- Fill the mold cavity with molten metal.
- Allow the metal to cool.
- Break away the sand mold and remove the casting.
Pattern and Mould 8 lectures 46:35 Types of pattern material The common materials of which the patterns are made are the following :
1) Wood : It is the most common material used for pattern making.
2) Metals : Metals are used with advantage, as pattern material, only when the number of castings to be made is very high and a closer dimensional accuracy is desired. They have a much longer life than wooden patterns and eliminate the inherent disadvantages of wood to a great extent.
3) Plastics : The plastics used as pattern materials are thermosetting resins. Phenolic resin plastic and foam plastic suit best for this purpose. For making the pattern, first the moulds are made, usually from plaster of Paris. The resin is then poured into these moulds and the two heated. At a specific temperature, the resin solidifies to give the plastic pattern.
4) Wax : Wax patterns are exclusively used in investment casting.
Pattern allowance A pattern is always made larger than the required size of the casting considering the various allowances. These are the allowances which are usually provided in a pattern.
1.Shrinkage or contraction allowance:The various metals used for casting contract after solidification in the mould. Since the contraction is different for different materials, therefore it will also differ with the form or type of metal.
2.Draft allowanceIt is a taper which is given to all the vertical walls of the pattern for easy and clean withdraw of the pattern from the sand without damaging the mould cavity. It may be expressed in millimeters on a side or in degrees. The amount of taper varies with the type of patterns. The wooden patterns require more taper than metal patterns because of the greater frictional resistance of the wooden surfaces.
3.Finish or machining allowanceThe allowance is provided on the pattern if the casting is to be machined. This allowance is given in addition to shrinkage allowance. The amount of this allowance varies from 1.6 to 12.5 mm which depends upon the type of the casting metal, size and the shape of the casting. The ferrous metals require more machining allowance than non ferrous metals.
4.Distortion or camber allowanceThis allowance is provided on patterns used for casting of such design in which the contraction is not uniform throughout.
5.Rapping or shaking allowanceThis allowance is provided in the pattern to compensate for the rapping of mould because the pattern is to be rapped before removing it from the mould.
Types of pattern The pattern can be classified in different types as per their design, some of those are mentioned below:
- Single Piece Pattern
- Two-Piece or Split Pattern
- Multipiece Pattern
- Match Plate Pattern
- Gated Pattern
- Sweep Pattern
- Loose Piece Pattern
- Skeleton Pattern
- Shell Pattern
- Segmental Pattern
Types of sand mould Molding sands can be classified into various types according to their use - backing sand, core sand, dry sand, facing sand, green sand, loam sand, parting sand, system sand.
Binders In order to make the casting
core structurally strong to withstand operating pressures, binders are used. The core binder refers to the chemical mixture which adheres the filler to provide the core strength. Hence, the core represents a composite comprising the filler and the binder.
Additives Sand additives are commonly used in molds and cores to reduce defects like veining, metal penetration and unacceptable surface finish. Historically, iron oxides have been the additives of choice, primarily red iron oxide (hematite, Fe2O3) and black iron oxide (magnetite, Fe3O4).
Properties of moulding sand The basic properties required in molding sand and core sand are
adhesiveness, cohesiveness, collapsibility, flowability, dry strength, green strength, permeability, refractoriness etc.
Methods of moulding Basically we have two types of moulding methods. One is hand moulding and another one is machine moulding.
Pattern and Mould. 8 lectures 46:35 Types of pattern material The common materials of which the patterns are made are the following :
1) Wood : It is the most common material used for pattern making.
2) Metals : Metals are used with advantage, as pattern material, only when the number of castings to be made is very high and a closer dimensional accuracy is desired. They have a much longer life than wooden patterns and eliminate the inherent disadvantages of wood to a great extent.
3) Plastics : The plastics used as pattern materials are thermosetting resins. Phenolic resin plastic and foam plastic suit best for this purpose. For making the pattern, first the moulds are made, usually from plaster of Paris. The resin is then poured into these moulds and the two heated. At a specific temperature, the resin solidifies to give the plastic pattern.
4) Wax : Wax patterns are exclusively used in investment casting.
Pattern allowance A pattern is always made larger than the required size of the casting considering the various allowances. These are the allowances which are usually provided in a pattern.
1.Shrinkage or contraction allowance:The various metals used for casting contract after solidification in the mould. Since the contraction is different for different materials, therefore it will also differ with the form or type of metal.
2.Draft allowanceIt is a taper which is given to all the vertical walls of the pattern for easy and clean withdraw of the pattern from the sand without damaging the mould cavity. It may be expressed in millimeters on a side or in degrees. The amount of taper varies with the type of patterns. The wooden patterns require more taper than metal patterns because of the greater frictional resistance of the wooden surfaces.
3.Finish or machining allowanceThe allowance is provided on the pattern if the casting is to be machined. This allowance is given in addition to shrinkage allowance. The amount of this allowance varies from 1.6 to 12.5 mm which depends upon the type of the casting metal, size and the shape of the casting. The ferrous metals require more machining allowance than non ferrous metals.
4.Distortion or camber allowanceThis allowance is provided on patterns used for casting of such design in which the contraction is not uniform throughout.
5.Rapping or shaking allowanceThis allowance is provided in the pattern to compensate for the rapping of mould because the pattern is to be rapped before removing it from the mould.
Types of pattern The pattern can be classified in different types as per their design, some of those are mentioned below:
- Single Piece Pattern
- Two-Piece or Split Pattern
- Multipiece Pattern
- Match Plate Pattern
- Gated Pattern
- Sweep Pattern
- Loose Piece Pattern
- Skeleton Pattern
- Shell Pattern
- Segmental Pattern
Types of sand mould Molding sands can be classified into various types according to their use - backing sand, core sand, dry sand, facing sand, green sand, loam sand, parting sand, system sand.
Binders In order to make the casting
core structurally strong to withstand operating pressures, binders are used. The core binder refers to the chemical mixture which adheres the filler to provide the core strength. Hence, the core represents a composite comprising the filler and the binder.
Additives Sand additives are commonly used in molds and cores to reduce defects like veining, metal penetration and unacceptable surface finish the pattern for...
